Repeat spacing mechanism for typewriters



Dec. 24, 1968 R R, GALLANT 3,417,848

REPEAT SPACING MECHANISM FOR TYPEWRITERS Filed Dec. 13, 1965 2 Sheets-Sheet 1 Q INYENTOR REGINALD R. GALLANT AGENT Dec. 24, 1968 R. R. GALLANT 3,417,848

REPEAT SPACING MECHANISM FOR TYPEWRITERS Filed Dec. 13, 1965 2 Sheets-Sheet 2 United States Patent 0 3,417,848 REPEAT SPACING MECHANISM FOR TYPEWRITERS Reginald R. Gallant, Bristol, Conn., assignor to Olivetti Underwood Corporation, New York, N.Y., a corporation of Delaware Filed Dec. 13, 1965, Ser. No. 513,460 6 Claims. (Cl. 19782) ABSTRACT OF THE DISCLOSURE A repeat spacing key through its operation causes a member to become operated under the tension of a spring and thereby will act on a carriage escapement to operate it to institute a full escapement step of a carriage. So long as said repeat spacing key is held operated said member is forcibly restored through carriage movement toward each new step position and is suddenly released for reoperation by said spring just before the end of each step movement is reached. Said member is additional to the carriage escapement and because it has mass the said spring is able to assert itself thereon only after a momentary delay so that the carriage will distinctly and reliably become arrested by the escapement at the conclusion of each repeat step movement which takes place while the repeat spacing key is held operated.

This invention relates to typewriters and other business machines wherein step-advances of a carriage are controlled to occur through operations of an escapement. More particularly the invention relates generally to devices already well known, whereby repetitive operations of an escapement may be caused to occur at the will of an operator through variedly controlling a space control or key.

It is highly desirable that such repetitive carriage spacing devices embody provision to control the repetitive operations to occur with a time beat which is constant and reasonably quiet. In prior machines repetitive escapement operations have usually been segregated through the employ of weight devices requiring reversal of motion to allow successive carriage advances. Obviously, such weight devices cause a slowed spacing speed of the carriage, produce a shock and noise, and provision thereof is costly.

The repeat escapement operating mechanism herein featured, derives the desired repeat operation segregations through a novel and simple mechanism which provides that each escapement step of the carriage be definitely terminated at the end of each instituted escapement as an incident to its normal operation and that each repetitive escapement operation arises under the control of the preceding step advance, but through a delayed escapement operating effect.

It is a general object of the invention to provide an efliciently operative, economically manufacturable repeat-operation escapement mechanism which spaces the carriage in successively halted, lively successive steps.

It is another object of the invention to provide a repeat operation escapement mechanism which for operative time beat does not rely on motion reversal of weight devices which cause excessive noise, wear and strain on parts and unnecessary vibrations.

Other objects and advantages of the invention will readily become apparent from the following description of a preferred embodiment thereof, and from the accompanying drawing, wherein:

FIG. 1 is a rear perspective view of the novel repeat escapement mechanism of the invention in its normal, carriage advancement checking condition;

FIG. 2 is a right-hand fractional side elevation of the repeat escapement mechanism of FIGURE 1, conditioned for automatic repeat spacing performance;

FIG. 3 is a rear perspective view showing the repeat spacing mechanism similarly as in FIGURE 1, but in a potential carriage intercepting state obtained resultant to a step-advance of the carriage in progress following the operation of a repeat spacing key; and

FIG. 4 is a rear elevation of a pallet escapement having the repeat spacing mechanism of the invention adapted thereto.

The invention is shown incorporated in a standard manual typewriter. Having now particular reference to the rear perspective view of FIGURE 1, such typewriter embodies a platen 10 carried on a platen frame of which a right end is shown at 11. The said carriage includes a rack bar 12 and is guided in a usual manner, not shown, for advance and return travel parallel to the direction in which said rack bar 12 extends. A draw band 13 is constantly under the influence of a spring motor 14, tending to advance the carriage and the rack bar 12 in the direction indicated on the latter. However, advance movement of said carriage is controlled by an escapement device of conventional structure which comprises a toothed escapement wheel 16 having a circular row of escapement faces 16 unitarily turnable with an axle 17 on an escapement frame structure 18. Said wheel 16, through a gear pinion 20, has geared association with said rack bar 12, a usual ratchet pawl on said wheel, not shown, meshing with said pinion 20 and providing that the rack 12 in its advance travel direction indicated by the arrow is in driving communication with the escapement wheel 16. Obviously, the just described structure, not shown, allows readily the movement of the carriage in return direction without restraint by the escapement wheel 16. Said escapement device comprises further an escapement or stepping dog 21 pivotally carried on a usual dog rocker 22, and having a face 21' for engagement with the faces 16' of the escapement wheel. The rocker 22 is pivoted on pintles 23 which are carried solidly in the escapement frame structure 18. The pull of the draw band 13 turns the wheel 16 normally to the limit permitted by the dog 21 engaging an abutment 24 on said rocker 22, Moreover, a spring 26 anchored to the frame structure at 27 is connected to the dog 21 to have a constant forward and leftward urge thereon in the machine. Said forward urge causes the rocker 22 normally to abut limitedly a stationary screw head indicated at 28, so that the upper end of the dog 21 is instrumental to cooperate with a tooth of the escapement Wheel 16 to hold the carriage against advance.

Single step advances of the carriage may be effected by operation of a usual single-space key, not shown. Such single-space key rocks the rocker 22 counter-clockwise in FIGURE 1 so as to swing the dog 21 transversely of the plane of the wheel 16, free of the engaged wheel tooth. Under the tension of the spring 26, the dog 21 will now swing on the dog rocker 22 rightwardly in FIG- URE l to the limit of a stop lug 29 on the rocker 22, and ready to move into a position to intercept by its face 21' the next wheel tooth. If the single space key is promptly released, the dog rocker 22 will swing promptly clockwise as seen from the front to assume the normal position shown in FIGURE 1. This places the dog 21 into the path of the advancing next escapement wheel tooth, the carriage then being halted by the dog 21 being driven by the wheel against the abutment 24 on the rocker 22. If the operator unduly dwells on the single-space key, the carriage will nevertheless start its advance step, and in doing so the said next tooth of the escapement wheel 16 will engage a usual beveled tooth 30 on the dog rocker 22 for the purpose of compelling the release of the type key and thereby assuring a single space advance of the carriage.

All the mechanism described to this point is conventional structure.

Repeat automatic spacing feature For repeat operation spacing control of the described escapement, there is pivotally carried on the outer ends of the pintles 23 a rockable member or element in the form of a bail structure 32. A repeat space key 33, see FIGURE 2, has a pivot point at 34 and includes an arm 31 which under the tension of a strong spring 35 has normally a possion against a stop 36. Said bail 32 has a resilient means in the form of a spring 37 associated with it, which spring tends to operate it from the FIGURE 1 to the FIGURE 2 position, but the restoring spring 35 for the repeat space key 33 is of such superior strength in respect to the spring 37 that the key arm 31 by contact with an arm 39 on the bail 32 maintains such bail normally restored. However, the spring 37 is enabled to operate the bail 32 whenever the repeat space key 33 is operated, and at such time a tongue 38 on the bail actuates the dog rocker 22 to the position seen in FIGURE 2, and this moves the dog 21 free of the escapement wheel tooth with which it had been engaged. Consequently, the dog 21 influenced by its spring 26, will now swing to the limit of the stop lug 29 just beyond the wheel tooth with which it had been engaged, and, for the time being, remains out of the plane of the escapement wheel 16. Meanwhile the urge of the spring motor 14 overcome the inertia of the carriage, so that the wheel 16 starts its step movement.

A first part of such step movement is utilized to effect the restoration of the bail 32. The means for accomplishing this comprises an element 41 pivotally borne on a bracket extension 43. Such element 41 is normally situated in any one of the notches formed by the teeth of the wheel 16. During each step advance of the escapement wheel, in a first portion of such step advance the swingable end of said element is displaced forcibly outwardly by a wheel tooth, as illustrated in FIGURE 3. Obviously, the spring motor 14 acts to advance the escapement Wheel 16 and thus supplies the power by which the element 41 is forcibly displaced. When so forcibly displaced said element 41 will act forcibly through an associating means in the form of a link 42 to impart a restoring movement to the bail 32 so that the dog rocker 22 under the influence of its spring 26 will forcibly become restored to its normal position and thereby will allow the stepping or escapement dog 21 to become spring drawn into the path of the wheel tooth with which it is required to coact to limit the step-advance of the carriage. From FIGURE 3 it will be seen that the element 41 has a dwell-end-portion 44, which, as the wheel 16 drives the dog 21 toward the limit stop 24, is instrumental to maintain for a short time interval the element 41 operated and thus to keep the bail 32 restored.

However, just before the step advance af the carriage is concluded by the escapement dog 21 being driven against the stop 24, the extremety of the element 41 clears the crest of the advancing escapement wheel tooth which has been coactive therewith. Thus the bail 32 can now again submit to the operating force of the spring 37 to become subject to reoperation. However, on one hand the carriage at this time has attained great speed and on the other hand the inertia of the bail 32 and the rocker 22 is such that the dog 21 becomes first driven against the stop 24, arresting the carriage, so that only following this the rocker 22 has a chance to become reoperated to effect an institution of a next step advance of the carriage. The mass of the bail or operable means 32 is so correlated to the operating bias of the spring 37, that each time such operable means becomes suddenly subject to reoperation by the operating bias of said spring 37, such operating bias is able to become effective only after the carriage has been intercepted by the cooperation of the escapement dog face 21 with a full escapement step defining tooth face 16 The rocker itself must be light in weight so as not to afford much resistance to the operations of the usual type bars in the machine. Obviously, so long as the repeat key 33 is held depressed, there will ensue full and uninterrupted step-advances of the carriage, each of which is distinctly terminated before another is instituted. It is to be realized that the interitia impact incident to each step arrest of the carriage, assures that the spring 37 is able to assert itself only each time after said impact subsides, which is very fast. Obviously, the carriage is momentarily halted at the conclusion of each carriage step and then proceeds on uninterruptedly to execute a next full step movement. When the operator rleases the repeat space key 33, the bail 32 immediately is forced to its normal position seen in FIGURE 1, and the element 41 becomes unable to exercise any control over the bail to cause a reporation of the escapement rocker 22.

It will be observed that the element 41 is conditionable by the operation of the repeat space key 33 through the operation of the bail 32 to be then subject to the control by the advance travel of the carriage to restore the operable bail 32 each time against the operating bias of the spring or resilient means 37. It is further to be observed that the notches in said escapement wheel or toothed member 16, relatively to said element 41, are arranged and of correlated forms so that in a first part of each step movement of the carriage the said element is adapted to be forced out of the notch and so in a very endapproach of any full step carriage position said element becomes free to enter into a next succeeding notch.

It is emphasized also that each repeat space is executed without an intermediate halt or slow down and coincides with the carriage step positions. Due to this the repeat spaces are discernable distinctly from each other at relatively fast intervals and the operator will be better able to release the repeat space key at the exact required time.

Preferably the link 42 has a pin and slot connection 45 with the element 41 which allows the latter normally to function in association with the escapement wheel as a reverse rotation check pawl. To serve in such capacity, the element 41 has a light spring 46 associated with it.

Single step-advances of the carriage may be obtained by momentarily tapping the repeat space key 33, so that the rocker imediately restores upon operation after the dog 21 has escaped the wheel tooth with which it has last been cooperative to halt the carriage.

Obviously, the basic feature of the invention whereby, following the initial operation of the escapement other operations of the escapement are caused to follow under control of the effected step advances of the carriage and with a time delay, is easily applicable to different kinds of escapement devices. This is demonstrated by way of example in FIGURE 4, wherein the escapement wheel, 16*- carried on an axle 17, is controlled by a pallet dog 47, the parts in said FIGURE being shown in their normal positions which prevail when the carriage stands arrested in a letter feed position. Upon depression of a repeat space key lever 33' which is pivoted at 34', an arm 49' of said lever rises against the urge of a spring 35 and permits an operation of a bell crank 32' through a strong spring 37. Said bell crank 32 under the tension of such strong spring 37' thus rocks the pallet 47 which has a relatively weaker space 47 clockwise in FIGURE 4, so that the wheel 16 is then freely allowed to turn in the direction of the arrow a fractional step. During such fractional step the hook-like part 47 which is intergral with the pallet 47, enters momentarily between the teeth of the escapement wheel 16*. On the other hand, while such fractional step takes place, a pivoted element 41' receives a counterclockwise displacement through a tooth on the escapement wheel 16 and restores by a nose 48 forcibly the bell crank 32 against the urge of the spring 37, whereby the pallet 47 and the associated hook-like part 47 becomes free to restore under the urge of spring 47' just as the step advance nears conclusion, the pivoted element 41' under the tension of its spring 46, will snap behind a passing wheel tooth, to the position seen in FIGURE 4, so that the nose 48 of the element 41 frees the bell crank 32 for reoperation by the spring 37 and so that with a time delay the bell crank 32 will resultingly reactuate the escapement pallet 47 to cause a next step advance of the escapement wheel 16 Obviously, additional operations and restorations of the pallet 47 will follow as long as the repeat space key 33 is held operated.

Moreover, it will be seen that whenever the repeat key 33 is released, the pallet 47 will be enabled to bring the escapement wheel to rest when the end of the started step-movement is reached.

The beveled tooth 47 FIGURE 4 is provided for the conventional purpose as the bevelled tooth 30 in the escapement shown in the other figures, namely for compelling in regular typing operations the release of type keys, and thereby to assure no more than a single step advance in accompaniment with each character that is being typed. All the parts 16*, 41, 32', 47 and 47 in FIGURE 4 are in the same plane, except that the part 47 has an offset portion 47, as indicated in FIGURE 4, to provide operating clearance for the part 41'. The spring 35' obviously serves to return the repeat key 33' to the shown normal position against a stop pin 36, for the same purpose as the spring 35 serves in the structure shown in FIGURE 1.

The invention obviously is appplicable also to rack escapements such as are disclosed in a patent to Crumrine No. 1,945,847, dated Feb. 6, 1934 and Thompson et al. No. 1,994,544, dated Mar. 19, 1935, the latter having alternately operated escapement dogs cooperating with a double pitch rack.

What is claimed is:

1. In combination with a machine embodying a carriage movable on a frame in advance and return directions, means constantly tending to advance said carriage and an escapement device associated with the carriage, comprising a toothed member having a row of full escapement step defining tooth faces and also comprising an escapement dog means having dog face means thereon for engagement with said escapement step defining tooth faces to halt the carriage in different full step carriage positions,

said escapement device being actuatable to disengage transitorily said escapement dog face means from any of said full escapement step defining tooth faces and thereby to cause the carriage to execute under the influence of said tending means single full step advances limitedly terminated by cooperation of said escapement dog face means with successive escapement tooth faces;

an operable and restorable repeat space key,

means additional to said escapement device, having mass and being bodily operable from a normal position to disengage said escapement dog face means from any escapement tooth face engaged therewith and conversely restorable to condition said escapement device for said escapement dog face means to intercept the carriage by cooperation with a next escapement tooth face,

resilient means controlled by the operation and the restoration of said repeat space key respectively to place a resilient operating bias and a resilient restoring bias on said bodily operable means, whereby operation of said repeat space key will cause said bodily operable means to control the escapement device to release the carriage for advancement and whereby the restoration of said repeat space key will cause said bodily operable means to control the escapement device to intercept the carriage by cooperation of said escapement dog face means with a next full escapement step defining tooth face as the carriage arrives at a next reached full step position,

and means conditionable by said bodily operable means for the duration of the operation of said repeat space key to be then subject to control by advance travel of the carriage to restore said bodily operable means each time against the operating bias of said resilient means as the carriage advances through nearly a full step movement, and thereafter each time suddenly immediately before the end of such full step movement is reached to render said bodily operable means subject to reoperation by the operating bias exerted thereon by the resilient means as the carriage completes its movement to the next full step position,

the mass of said bodily operable means being so correlated to the operating bias of said resilient means that each time said bodily operable means becomes suddenly subject to reoperation by said operating bias of said resilient means, such operating bias is able to become effective on said bodily operable means only after the carriage has been intercepted by the cooperation of said escapement dog face means with a full escapement step defining tooth face,

whereby so long as said repeat space key is held operated, the said escapement device will become reoperated by the operating bias of said resilient means each time after the carriage is momentarily solidly and distinctly halted at a full step position by a cooperation of said escapement dog face means with a full escapement step defining tooth face.

2. The invention set forth in claim 1, said conditionable means including said toothed member,

said toothed member having notches at intervals correlated to the escapement tooth faces,

an element movably mounted to enter into said notches,

the notches in said toothed member relatively to said element being arranged and of correlated forms so that as the carriage advances through nearly a full step movement the said element will be forced out of a notch and so that in a very end approach of any full step carriage position said element becomes free to enter into a next succeeding notch,

and means associating said bodily operable means with said element so that so long as said repeat space key is operated, said bodily operable means will be restored by said element against the operating urge of said resilient means each time the carriage moves through nearly said full step movement and so that conversely under the bias of said resilient means, said operable means will become subject to reoperation by said resilient means as said element becomes free to enter into a next notch of the toothed mem her but with delayed effect only after the carriage first becomes momentarily and distinctly halted by cooperation of said escapement dog face means with a full escapement step defining tooth face.

3. The invention set forth in claim 2,

and a light spring associated with said element and urging it into the notches of said toothed member,

said toothed member being an escapement wheel which is rotatable by advance travel of the carriage,

and said associating means when disposed in its normal unoperated position while said repeat space key stands unoperated, affording operating clearance for said element for the latter to serve normally as a reverse rotation check for said escapement wheel.

4. In combination with a machine embodying a carriage movable on a frame in advance and return directions, means constantly tending to advance said carriage, and an escapement device associated with the carriage, comprising a toothed member having a row of full escapement step defining tooth faces and also comprising an escapement dog means having dog face means thereon for engagement with said escapement step defining tooth faces to halt the carriage in different full step carriage positions,

said escapement device being actuatable to disengage transitorily said escapement dog face means from any of said full escapement step defining tooth faces and thereby to cause the carriage to execute under the influence of said tending means full single step advances limitedly terminated by cooperation of said escapement dog face means with successive escapement tooth faces;

means additional to said escapement device, being bodily operable from a normal position to disengage said escapement dog face means from any escapement tooth face engaged therewith and conversely restorable to condition said escapement device for said escapement dog face means to intercept the carriage by cooperation with a next escapement tooth face,

resilient means associated with said bodily operable means to urge it constantly toward operated position,

a repeat space key being one-way operative on said bodily operable means to hold it normally in its unoperated position against the urge of said resilient means,

spring means associated with said repeat space key and being so strong relatively to said resilient means to urge normally said repeat space key and said bodily operable means against the urge of said resilient means to their normal positions,

whereby upon operation of said repeat space key the said resilient means operates said bodily operable means, and whereby upon the release of said repeat space key said bodily operable means becomes restored by said spring means and cause said escapement device to intercept the carriage through said escapement dog face means engaging a next tooth face,

and means conditionable by said bodily operable means for the duration of the operation of said space repeat key to be then subject to control by advance travel of the carriage through each full step to render said bodily operable means each time restored against the urge of said resilient means as the carriage advances through nearly a full step movement, and thereafter each time suddenly immediately before the end of such full step movement is reached to render said bodily operable means subject to reoperation by the urge of said resilient means as the carriage completes its movement to each next full step position,

the mass of said bodily operable means being so correlated to the operating bias of said resilient means that each time said bodily operable means becomes suddenly subject to reoperation by said operating bias of said resilient means, such operating bias is able to become effective on said bodily operable means only after the carriage has been intercepted by the cooperation of said escapement dog face means with a full escapement step defining tooth face,

whereby so long as said repeat Space key is held operated, the said escapement device will become reoperating by the operating bias of said resilient means each time after the carriage is momentarily solidly and distinctly halted at a full step position by a cooperation of said escapement dog face means with a full escapement step defining tooth face. 5. In combination with a machine embodying a carriage movable on a frame in advance and return directions, means constantly tending to advance said carriage, and an escapement device associated with the carriage, comprising a toothed member having a row of full escapement step defining tooth faces, an escapement rocker and a stepping dog carried on said rocker for movement between an escapement step limiting position and an extended position, said stepping dog normally being cooperative with different f-ull escapement step defining tooth faces of said toothed member to hold the carriage in different full step positions, and being responsive to transitory operation of said rocker to halt the carriage through cooperation with any next succeeding full escapement step defining tooth face,

an operable and restorable repeat space key, means additional to said escapement device, being bodily operable from a normal to an operated position, to operate said rocker, and being restorable conversely to cause a restoration of said rocker,

resilient means controlled by the operation and restoration of said repeat space key respectively to place a resilient operating bias and a resilient restoring bias on said bodily operable means, whereby operation of said repeat space key will cause an operation of said rocker to free the carriages to execute an advance step and whereby the restoration of said repeat space key will cause a restoration of said rocker to cause said stepping dog to intercept the carriage by cooperation with a next succeeding full escapement step defining tooth face as the carriage reaches a next full step position,

said toothed member having notches at intervals correlated to said escapement teeth,

an element independent of said rocker, movably mounted to enter into said notches,

the notches in said toothed member relatively to said element being arranged and of correlated forms so that as the carriage advances through nearly a full step movement, the said element will be forced out of a notch and so that in a very end approach of any full step carriage position said element becomes free to enter into a next succeeding notch,

and means associating said bodily operable means with said element so that so long as said repeat space key is held operated, said bodily operable means will be restored by said element against the urge of said resilient means each time the carriage moves through nearly said full step movement and so that conversely under the bias of said resilient means said bodily operable means will become suddenly subject to reoperation by said resilient means as the carriage in its movement to a next full step position very closely nears such position,

the mass of said bodily operable means being so correlated to the operating bias of said resilient means, that each time said operable means becomes suddenly subject to reoperation by said operating bias of said resilient means, such operating bias is able to become effective on said bodily operable means only after the carriage has been intercepted by the cooperation of said stepping dog with an escapement step defining face of the toothed member,

whereby so long as said repeat space key is held operated, the said escapement device will become reoperated by said resilient means each time after the carriage is momentarily solidly and distinctly halted at a full step position by a cooperation of said stepping dog with one of the tooth faces on the toothed wheel.

References Cited UNITED STATES PATENTS 744,424 11/1903 Steiger 197-85X 937,336 10/1909 Stickney 19782 McLaughlin 19784 Rohrer 19782 Page 19788 Canny 19782 ROBERT E. PULFREY, Primary Examiner.

E. T. WRIGHT, Assistant Examiner. 

